I was nervous to see who would be in my classes and what my teachers would be like, but after the day had gone by I had a feeling that it would be a great year.

MY QUESTION: Would there be a comma after "by" or after "but"?

I would use "however" instead of but; put a semi-colon after it and use a comma after "by".

To determine whether there should be a comma after "by" or after "but" in the sentence, we need to understand the rules for using commas in compound sentences.

The sentence "I was nervous to see who would be in my classes and what my teachers would be like, but after the day had gone by I had a feeling that it would be a great year" is a compound sentence because it combines two independent clauses ("I was nervous to see who would be in my classes and what my teachers would be like" and "after the day had gone by I had a feeling that it would be a great year") using the coordinating conjunction "but".

When connecting two independent clauses with a coordinating conjunction like "but," you generally use a comma before the coordinating conjunction. Therefore, there should be a comma after "by" in the sentence:

"I was nervous to see who would be in my classes and what my teachers would be like, but after the day had gone by, I had a feeling that it would be a great year."

Remember, using commas correctly can help clarify the meaning of your sentences and make your writing more effective.